Oil wells generally comprise a positive pressure pump located beneath the surface within the oil source, which pump is mechanically operated from the surface by a rod string operated by a walking beam apparatus. The top of the rod string passes into the well casing at the surface well head through a "stuffing (or packing) box", and the upper portion of the rod string is enclosed in a "polish (or polished) rod" which provides a smooth surface to wear against the seal(s) in the stuffing box.
Normally, several such pumps are in continuous operation at remote sites, monitored only at a central location by a human observer. Moreover, the harsh environment at the well head (corrosive chemicals, sand and abrasives, etc.) can cause the packing or seals in the stuffing box to deteriorate rapidly, thereby allowing oil to gather on the polish rod and be drawn upward past the worn seals and be thrown about the immediate environment due to the reciprocating action of the rod. The Environmental Protection Agency has developed strict regulations against such occurrences, and consequently oil well owners have almost universally equipped wells with various devices to prevent the escape of oil residue from worn stuffing box seals.
However, the various devices developed thus far are relatively complex assemblies of specially machined, cast or forged components, and are generally constructed to withstand relatively high pressures. Such devices are excessively costly and redundant in view of the stuffing box which is already located at the well head.
What is needed is a simple, low pressure means of containment of any oil spillage or residue resulting from worn seals or packing at the stuffing box of an oil well head. The device must be capable of being quickly and easily installed about the stuffing boxes of most existing well heads, and must further serve to collect and contain a reasonable volume of spillage to preclude its escape to the surrounding environs. Moreover, the device must provide a warning and/or shut down the pump in the event of fluid accumulation beyond a predetermined level.